Water-base rust preventive and lubricant



WATER-BASE RUST PREVENTIVE AND LUBRICANT Michael J. Furey, Berkeley Heights, N.J., assignor to Esso Research and Engineering Company, a corporation of Delaware No Drawing. Filed Nov. 23, 1956, Ser. No. 623,765

'5 Claims. (Cl. 252-40) This invention relates 'to Water-base rust preventive compositions having lubricating properties. Particularly, it relates to a water-base rust preventive and lubricant having outstanding rust preventive properties and good load carrying ability, which comprises metal soaps of paraflinic acids, oil, and an organic phosphate.

The water-base compositions of this invention are nonfiammable and may be used either to lubricate or prevent corrosion, or both. They may be used to preventcorrosion of inaccessible systems, such as circulating and hydraulic systems; or to protect metal parts such as newly machined metal pieces, bearings and instruments, metal stampings, etc., during processing or storage. They may also be used as metal working fluids such as cutting oil-s' or as a general lubricant.

]-The compositions of this invention consist of water mixed with an emulsifiable concentrate comprising a mixed sodium-barium soap of oxidized petrolatum, an alkyl phosphate and oil.

The soaps useful in this invention are mixed sodiumbarium soaps of parafiinic acids formed by the oxidation of petroleum petrolatum. Any petroleum petrolatum may be used in preparing the parafl'inic acids as the specific petrolatum used is not critical. Generally p etrolatum is prepared by the solvent-dewaxing of a parafi'lnic crude oil, and generally will have a viscosity at 210 F. of about 65 to 73 SUS and a penetration at 77 F. according to the ASTM D-937 method of about 175 to 215 mm./ 10. The petrolatum is oxidized to convert it to parafiinic acids by blowing with air or oxygen, at elevated temperatures, with or without a catalyst. The oxidation is normally continued until an ASTM saponification number of from 60 to 110 mg. KOH/gm. oxidized petrolatum and an ASTM acid number of from 20 to 50 mg. KOH/ gm. oxidized petrolatum are attained.- Preparation of petrolatum and oxidized pertolatum are well known in the art and forms no part of this invention.

Thesodium and barium soaps are then generally formed by reacting the oxidized petrolatum mixture with sodium wherein R represents an alkylradical and R represents either hydrogen or an alkyl radical, saidalkyl radicals: containing between about 3 to 20, e;g., 4 to 12 carbon atoms'per radical. The total number of carbon atoms phate, mono-C Oxo di-acid phosphate, mono-cetyl diacid phosphate, mono-octadecyl di-acid phosphate, di-' octadecyl mono-acid phosphate.

The alkyl phosphates are generally commercially available as equilibrium mixtures of monoand di-alkyl estersof phosphoric acid formed by the reaction of phosphoric anhydride and alcohol, as typified by the following equation:

21 0 +6ROH 2(RO) P(O)OH+2ROPO(OH) wherein R represents a C to C e.g., C to C12 alkyl" radical. The alcohol may be either primary or secondary,

branched-chain or straight-chain. Operable alcohols include iso-propyl, n-propyl, butyl, amyl, methyl isobutyl carbinol, Z-ethyl hexyl, iso-oetyl, oetadecyl, cetyl alcohol, etc. Mixtures of alcohols may also be used such as amixture of propyl and butyl alcohol. Also included are i mole of P 0 The reaction is well known in the artand is usually performed by simple mixing of the alcohol and P 0 The reaction product may be used without further purification. In the event that the alcohol is a solid, then the alcohol may be melted before the P 0 is added; or: the reaction may be carried out in the presence of aninert solvent in which the solid alcohol dissolves. In-the latter case, the solvent is removed by stripping after the reaction is completed. The reaction is usually: fairly rapid, being completed when no more of the powdered P 0 is observed. The reaction takes from5 minutesto. 2 hours, usually 10 to minutes for completion. "The reaction is exothermic and thertemperature may be controlled by cooling or by the slow addition of the P20 so; as to keep the temperature of the reaction mixture below 100 C. in order to prevent decomposition of the alky phosphate.

A suflicient amount of oil is incorporatedinto the com-- position to insure the formation of a water-in-oil emulsion when water is added. Any non-volatile oil may be 7 used including mineral oil, synthetic oils, or vegetable oranimal oils.

The rust preventive compositions of this invention comprise a major proportion of water, say about 60 to 99 wt.

percent, e.g., to wt. percent and about 1 to 40 wt. percent, e.g., 10 to 20 wt. percent of an emulsifiable concentrate. The emulsifiable concentrate comprises about 30 to 50 wt. percent., e.g., 35 to 45 wt. percent of the mixed sodium and barium soaps of oxidized petrolatum; about 10.to 25 wt. percent, e.g., 15 to 20 wt. percent of the alkyl phosphate, the balance of the concentrate being oil.

The invention will be further understood by the following examples.

EXAMPLE I a A concentrate was prepared by simple mixing of thefollowing:

(a) 5 parts by weight of a mixed sodium/barium soap of oxidized petroeum petrolatum. The weight ratio of sodium to barium in the soap was 3.8 parts by weight:

I of sodium-per 1 part by weight of barium. T he 'sodium/ 5 Patented Nov. 8 1960 barium soap had an acid number of 12.1 mg. KOH/gm. of soap, and a saponification number of 31.4 mg. KOH/ gm. of soap. The soap was prepared from petrolatum oxidized to an acid number of 28 mg. KOH/ gm. oxidized petrolatum, and a saponification number of 93 mg. KOH/ gm. oxidized petrolatum.

(b) 2 parts by weight of a mixture of monoand di- C Oxo phosphate obtained by the reaction of 1 mole of P and 4 moles of a C Oxo alcohol prepared from a copolymer of propylene and butylene. The reaction product was formed by simple mixing of the P 0 in the alcohol until a clear product was obtained. This product was used without further purification.

(c) 5 parts by weight of a mineral oil which was a naphthenic coastal distillate having a viscosity of 105 SUS at 100 F. and 39 SUS at 210 F.

An emulsion was prepared containing 12 wt. percent of the above concentrate and 88 wt. percent water. The emulsion was very stable, as no separation occurred after storage of a sample for one month, at room temperature.

Although the emulsion was milky white in appearance, it dried, when coated on metal specimens, to form an almost invisible thin film. For example, when the emulsion was applied to steel panels by dipping, the coating dried in about an hour to form a film of about 0.0001 inch average thickness. Although this film is deposited by water, it nevertheless serves as an excellent protective barrier against moisture as illustrated by the following tests.

Humidity cabinet test.-Sand-blasted steel panels (2" x 4") were immersed in the test fluid for one minute, removed and allowed to hang for 4 hours at 77 F. The panels were then hung in the JAN-H-792 Humidity Cabinet (95-100% relative humidity and 120 F.) and were then examined periodically for rusting.

Shed storage test.-A shed storage test was carried out according to the method of Federal Specification MIL- C-16173A. In this test, sand-blasted steel panels were immersed in the test fluid for one minute, removed and then allowed to drain for 24 hours at 77 F. The panels were then placed in a louvred shed and were inspected at various intervals for signs of rusting.

Direct outdoor exposure test-Polished steel panels were dipped into the test fluid for one minute, removed and were permitted to drain for 24 hours at 77 F. These panels were then mounted vertically on a rack and were placed uncovered on the roof of a building. After 30 hours exposure, including some snow and rain, the panels were removed and examined for corrosion.

For comparison purposes, the above tests were also run on unprotected metal panels, and on metal panels coated respectively with: a mineral oil, a commercial oiltype rust preventive, and a commercial solvent-type rust preventive. The results of these tests are shown in the following table:

ordinary oil and was superior to the two typical commercial types of rust preventives.

It has also been found that the water-base material of this invention is equally effective when applied to either dry or wet steel surfaces. This is of particular advantage in many applications where the metal may be wet, e.g. in pickling and washing operations, since it eliminates the need for drying the metal before applying the rust preventive. The water-displacing ability of the composition of the invention is illustrated by the following test.

Ability to protect wet steel surfaces.-Polished steel panels were immersed in water for one minute, removed and immediately plunged into each of the test fluids for 5 seconds. The panels were then withdrawn from the test fluid, hung up, and examined periodically for corrosion.

The results of this test are shown in Table II which follows:

Table II.Efiect of fluids on protecting wet steel from rusting Treatment of Wet Steel Appearance of Steel After Treatment Rust appears within 10 minutes. Panels had 18 to 22 rust areas averaging 54 in diameter.

Rust appears within 15 minutes. Panels had 120 to 150 rust areas averaging Me" in diameter.

N o rust after 20 hours.

None

Mineral lubricating oil (same as in Table I).

Emulsion of Example I Lubricating properties.-The product of the invention was also tested for lubricating and extreme pressure properties. This test was carried out in the 4-Ball E.P. Lubricant Test. The results of this test are given in Table III.

Table III.Lubricating properties 4-Ball E. P.

Maximum load that can be carried for one minute without film failure or seutfing, using steel balls.

Not only have the materials of the invention excellent rust preventive properties, but as seen from the above table, they have excellent lubricating properties.

What is claimed is:

1. A rust preventive concentrate consisting essentially Table I.Efiect of various fluid coatings on the corrosion of steel Emulsion Commercial of Bare Panel Mineral Oil Commercial Oil-type Solvent-Type Example I Rust Preventive Rust Preventive Humidity Cabinet Life 1 (in hour 1000+-.-" 1 1000+ 120-600. Shed Storage Exposure-Amount of rust on panel after:

4 days None Light Non None None. 9 days... (1 Light Medium 50/50 spots Yellow stain Do. 15 days 100%t light scattered 400/500 spots.. Yellozv stain 40/200 Do.

rus spo s. Outdoor Exposure: Area of surface 95% heavy rust heavy rust. heavy rust Do.

rusted after 30 hours.

1 Time before rusting or corrosion observed according to Specification MILCl6173A definition. 9 Some evidence of a very light gray stain-probably the early stages of corrosion.

As seen from the above table, the emulsion of the invcntion gave excellent all-around rust preventive protecof mineral lubricating oil, 30 to 50 wt. percent of a mixture of sodium and barium soaps of oxidized petrolatum,

tion. The emulsion showed great superiority over 75 wherein said soaps contain about 0.5 to 20 parts by weight of sodium per part by weight of barium, said mixed soaps having an acid number of 4 to 20 mg. KOH/ gm. of soap and a saponification number of to 60 mg. KOH/gm. of soap, said soap being prepared from an oxidized petrolatum having an ASTM saponification number of about 60 ot 110 and an ASTM acid number of about to 50, and about 10 to wt. percent of an oil-soluble phosphate selected from the group consisting of monoand di-alkyl phosphates and mixtures thereof containing a total of about 3 to carbon atoms and wherein said alkyl radicals each contain 3 to 20 carbon atoms.

2. A rust preventive concentrate according to claim 1, wherein said oil-soluble phosphate is a mixture of monoand di-octyl phosphates.

3. A rust preventive concentrate consisting essentially of mineral lubricating oil, 35 to wt. percent of a mixture of sodium and barium soaps of oxidized petrolatum, wherein said soaps contain about 1.0 to 10 parts by weight of sodium per part by weight of barium, said mixed soaps having an acid number of 8 to 16 mg. KOH/ gm. of soap and a saponification number of 20 to 40 mg. KOH/ gm. of soap, said soap being prepared from an oxidized petrolatum having an AST M saponification number of about 60 to 110 and an ASTM acid number of about 20 to 50, and about 15 to 20 wt. percent of an oil-soluble phosphate selected from the group consisting of monoand di-alkyl phosphates and mixtures thereof containing a total of about 8 to 24 carbon atoms and wherein said alkyl radicals each contain 4 to 12 carbon atoms.

4. A rust preventive and lubricating composition consisting essentially of 60 to 99 wt. percent of water and 1 to 40 wt. percent of an emulsifiable concentrate, said emulsifiable concentrate in turn comprising mineral lubricating oil, 30 to wt. percent of a mixture of sodium and barium soap of oxidized petrolatum, wherein said soaps contain about 0.5 to 20 parts by weight of sodium per part by Weight of barium, said mixed soaps having an acid number of 4 to 20 mg. KOH/ gm. of soap and a saponification number of 10 to mg. KOH/gm. of soap, said soap being prepared from an oxidized petrolatum having an ASTM saponification number of about 60 to and an ASTM acid number of about 20 to 50, and about 10 to 25 wt. percent of an oil-soluble phosphate selected from the group consisting of monoand di-alkyl phosphates and mixtures thereof containing a total of about 3 to 40 carbon atoms and wherein said alkyl radicals each contain 3 to 20 carbon atoms.

5. A rust preventive composition comprising a major proportion of Water and a rust preventive proportion of the composition of claim 1.

References Cited in the file of this patent UNITED STATES PATENTS 2,080,299 Benning et a1 May 11, 1937 2,224,695 Prutton Dec. 10, 1940 2,285,853 Downing et al June 9, 1942 2,637,695 McKinley et al May 5, 1953 2,653,909 Frazier Sept. 29, 1953 2,727,005 McKinley et al Dec. 13, 1955 2,779,737 Koft et a1 Jan. 29, 1957 FOREIGN PATENTS 462,563 Canada Jan. 17, 1950 617,404 Great Britain Feb. 4, 1949 OTHER REFERENCES Zimmerman et al.: Handbook of Material Trade Names, 1953, pub. by Industrial Research Service, Dover, N.H., p. 36. 

1. A RUST PREVENTIVE CONCENTRATE CONSISTING ESSENTIALLY OF MINERAL LUBRICATING OIL, 30 TO 50 WT. PERCENT OF A MIXTURE OF SODIUM AND BARIUM SOAPS OF OXIDIZED PETROLEUM, WHEREIN SAID SOAPS CONTAIN ABOUT 0.5 TO 20 PARTS BY WEIGHT OF SODIUM PER PART BY WEIGHT OF BARIUM, SAID MIXED SOAPS HAVING AN ACID NUMBER OF 4 TO 20 MG. KOH/GM. OF SOAP AND A SAPONIFICATION NUMBER OF 10 TO 60 MG. KOH/GM. OF SOAP, SAID SOAP BEING PREPARED FROM AN OXIDIZED PETROLATUM HAVING AN ASTM SAPONIFICATION NUMBER OF ABOUT 60 TO 110 AND AN ASTM ACID NUMBER OF ABOUT 20 TO 50, AND ABOUT 10 TO 25 WT. PERCENT OF AN OIL-SOLUBLE PHOSPHATE SELECTED FROM THE GROUP CONSISTING OF MONOAND DI-ALKYL PHOSPHATES AND MIXTUES THEREOF CONTAINING A TOTAL OF ABOUT 3 TO 40 CARBON ATOMS AND WHEREIN SAID ALKYL RADICALS EACH CONTAIN 3 TO 20 CARBON ATOMS.
 4. A RUST PREVENTIVE AND LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF 60 TO 99 WT. PERCENT OF WATER AND 1 TO 40 WT. PERCENT OF AN EMULSIFIABLE CONCENTRATE, SAID EMULSIFIABLE CONCENTRATE IN TURN COMPRISING MINERAL LUBRICATING OIL, 30 TO 50 WT. PERCENT OF A MIXTURE OF SODIUM AND BARIUM SOAP OF OXIDIZED PETROLEUM, WHEREIN SAID SOAPS CONTAIN ABOUT 0.5 TO 20 PARTS BY WEIGHT OF SODIUM PER PART BY WEIGHT OF BARIUM, SAID MIXED SOAPS HAVING AN ACID NUMBER OF 4 TO 20 MG. KOH/GM. OF SOAP AND A SAPONIFICATION NUMBER OF 10 TO 60 MG. KOH/GM. OF SOAP, SAID SOAP BEING PREPARED FROM AN OXIDIZED PETROLATUM HAVING AN ASTM SAPONIFICATION NUMBER OF ABOUT 60 TO 110 AND AN ASTM ACID NUMBER OF ABOUT 20 TO 50, AND ABOUT 10 TO 25 WT. PERCENT OF AN OIL-SOLUBLE PHOSPHATE SELECTED FROM THE GROUP CONSISTING OF MONO- AND DI-ALKYL PHOSPHATES AND MIXTURES THEREOF CONTAINING A TOTAL OF ABOUT 3 TO 40 CARBON ATOMS AND WHEREIN SAID ALKYL RADICALS EACH CONTAIN 3 TO 20 CARBON ATOMS. 